Forming tube for glass fibers



June 1967 MCCLEERY B. CUNNINGHAM E'TAL 3,32

FORMING TUBE FOB GLASS FIBERS Filed Sept. 15, 1966 bevmz-T l INVENTORS:MQCLEEEH/ B. CUNNINGHAM N %M 5 E M C W m United States Patent 3,323,751FORMING TUBE FOR GLASS FIBERS McCleery B. Cunningham and Charles K.Dunlap, Jr.,

Hartsville, S.C., assiguors to Sono'co Products Company, Hartsvilie,S.C., a corporation of South Carolina Substituted for abandonedapplication Ser. No. 478,718,

Aug. 10, 1965. This application Sept. 15, 1966, Ser. No;

Claims. (Cl; 242-11832) This invention relates to glass fibermanufacturing and more particularly to a carrier or formingtube for usein the winding of freshly spun glass filaments or fibers.

In the spinning of glass fibers to be processed into textile materialsuch as yarn and the like, glass in a molten condition is drawn throughsmall openings or orifices in a plate commonly referred was aspinneretinto the form of continuous filaments which solidify uponcontact withthe air. These continuously drawn filaments are wound onto atubular carrier in the form of aflexible' cylindrical sleeve which isgenerally referred to as a forming tube. In a glass fiber spinningoperation, this forming tube is slipped onto a spindle or the like whichis rotated at very high speeds, frequently around 8;000 to 10,000 rpm.and up, and the glass filaments are drawn from-the spinneret and woundon the tube at a relatively high linear speed generally 10,000 to 12,000feet per minute and'more. These forming tubes are used not only for sucha'winding operation but for subsequent winding and unwinding operationsas Well.

Due to the high speed at which the forming tubeis rotated and the ruggedconditions ofuse to which it is subjected, these tubes must meet rigidstandards and preferably should be of a suitable design and material soas not only to be inexpensive in initial costbut to be capable ofrepeated use. Furthermore, these forming tubes must be provided withexternal surface characteristics specifically suitable for-the glassfiber winding and unwindingoperations for which they are used. Ingeneral, it can be said that such tubes are required to have arelatively smooth peripheral surface to permit the glass fibers to bereadily unwound from the tube and at the same time this peripheralsurface should be' sufficiently rough so'that satisfactory winding ofthe fibers on the tubemay be accomplished. In addition, these tubesshould also be of light weight to avoid deformation by centrifugal forcewhich at the speeds referred to above is of a' substantial magnitude.Furthermore, these forming-tubes shouldbe highly resistant tocompression by the fibers Wound'tightly on the tube so that thetubemaintains its shape after removal from the spindle and the tubeshould have sufficient flexibility and elasticity to permit their readyremoval from the wound package of glass fibers when the tube'is to bereused. 7

Two commonly employed materials in u'setoday for making such formingtubes are plain paper or paperboard and plastic such as polyethyleneboth of which have objectionable features. Although a forming tubecomposed solely of ordinary paperboard generally performs satisfactorilythe first time it is used, its inherent lack'of strength and lack offlexibility causes it to deteriorate rapidly when reused. It is'thoughtthat the rapid deterioration of such paper forming tubes occursprimarily'as a result of the breaking of the cellulosic fibers inthetube resulting from the bending and folding to which such pa pertubes are subjected. Therefore, forming tubes of fibrous material suchas paper or paperboard are generally discarded after a few uses or evenafter a single use adding considerably to the manufacturing costs ofsuch glass fibers even though the initial cost of such paper tubes islow. Forming tubes of plastic have also been used with some success butthe severe stresses'to which plastic forming tubes are subjectedfrequently causes plastic tubes to disintegrate or explode during'useprimarily as a result of centrifugal force not only creating a hazardbut, as' a result of the high initial cost of such plastic tubes, addingconsiderably to manufacturing costs.

Accordingly, a primary object of this invention is to provide a new andnovel non-rigid forming tube for use in the Winding of glass filamentsor fibers.

Another object of this'invention is to provide a new and novel non-rigidforming tube for winding glass fibers which employs a minimum amount ofinexpensive materials to provide a forming tube of great strength andflexibility capable of repeated use.

A further object of this invention is'to provide a new and novelnon-rigid forming tube for winding glass fibers formed of fibrousmaterialwhich'is low in initial cost, which is easily manufactured onconventional winding apparatus and which contains a highly suitablewinding surface for glass fibers.

Still another object of this" invention is to provide a new and novelnon-rigid forming tube for glass fibers which is formed from two typesof'fibrous material, the combinationof which produces a forming tube'ofhigh strength and great flexibility; I

Other objects and advantages of'the invention Will'becomeapparent fromthe following' description taken in connection with the accompanyingdrawing.

In general, the objects of this invention and'othe'r related objects areaccomplished by spirally winding atleast one strip of'fibrous materialsuch as paper into a paper tube. A strip of non-woven textile materialimpregnated with a suitable resin is then spirally wound over the woundpaper'tube and the resin is permitted to cure. The resin in the plyof'non-woventextile material adhesively secures hard, irregularlyroughened outer surface. The forming tube is flexible to permit it to becollapsed longitudinally forremoval of the tube from thepackage of'glassfiberswound thereon.

The novel featureswhich arebelieved to be'ch'aracteristic of theinvention are set forth with particularity in the appended claims. Theinventionitself, however; both as to its organization and methodofoperation' may be best understood by reference to the followingdescription taken in conjunction with the accompanying drawing in which:

FIGURE 1 is a diagrammatic illustration of a tube winding apparatus forwinding-the forming tube'of the invention;

FIGURE 2 is a sectional view'taken substantially along line 22 of FIGURE1 in the direction of the arrows;

FIGURE 3 is an enlarged isometric view of the tube of the inevntion aswound with the apparatus of FIGURE 1; and

FIGURE 4 is an enlarged sectional view taken substantially'alongline 4-4of FIGURE 3 in'the direction of the arrows.

Referring now to the drawing and to FIGURE 1 in'particular, there isshown diagrammatically a typical spiral tube winding apparatus bymeansof which the winding of the forming tube of the invention is carriedout. As previously stated, the forming tube of the invention, which isshown in section and designated generally by the numeral 11 in FIGURE 4,is of the type which is particularly suitable for use in the winding offreshly spun glass filaments or fibers drawn from the spinneret of aglass furnace. However, the tube 11 of the invention may also beemployed in other glass fiber manufacturing operations involving glassfiber winding and take-off procedures.

As generally illustrative of the method of winding the forming tube 11of the invention, the conventional spiral tube winding apparatus ofFIGURE 1 is designated generally by the numeral 12. This spiral tubewinding appara-- tus 12 is shown carrying out a winding operation bymeans of which a continuous tube T advanced in the direction of thearrow I is produced. The tube T is cut into suitable lengths to form theforming tube 11 of the inven-r 7 tion as will be explained hereinafter.

As is well known, the spiral tube winding apparatus 12 comprises a frame13, a stationary mandrel 14 supported on the frame, a flexible endlessbelt 16 extending around a pair of pulleys 17 atleast one of which isdriven for rotating and advancing the tube T as it is formed and acutofi device 18 for cutting the continuously wound tube T into uniformsections of a selected length.

In the winding of the continuous tube T, at least one strip 21 offilbrous material or paper unwound from a supply roll 22 is first woundon the tube making mandrel 14. Preferably two such paper strips areemployed and accordingly a second paper strip 23 unwound from a supplyroll 24 is wound in overlying staggered relationship with and at thesame angle as strip 21 from the opposite side. of the mandrel 12. Asshown in FIGURE 1, the angle at which the paper strips 21, 23 are woundonto the mandrel 14 is preferably between 35 and 50 degrees relative tolongitudinal axis of the mandrel 14 and, in the illustrated embodiment,the strips 21, 23 are wound at an angle of approximately 40 degrees.

In order to adhere the paper strips 21, 23 together in the spirallywound relationship, the paper strip 23 is advanced in contact with anapplicator roll 26 suitably supported for rotation in a receptacle 27containing a suitable adhesive in the well known manner. Thus, theapplicator roll 26, as it rotates, applies adhesive to the underside ofstrip 23. Contact between the strip 23 and the applicator roll 26 ismaintained by advancing the strip 23 under guide rollers 28, 29 alsosuitably supported for rotation on the receptacle 27.

In this manner, the two paper strips 21, 23, spirally wound withadhesive therebetween, form a two ply tube 31 which is advanced underthe belt 16 in the direction of the arrow I. The paper strips 21, 23 arepreferably each wound with the edges of adjacent convolutions in anabutting relationship. Paper tube 31 therefore contains a spiral buttseam 23a as shown best in FIGURE 3.

As the paper tube 31 advances along the mandrel 14 down from the belt16, a spirally wound outer ply 32 of non-woven textile materialimpregnated with a suitable resin is wound in overlying relationshipwith the wound paper ply 23 of the wound paper tube 31. Strip 32 may beany suitable non-woven textile material Which-is readily availablecommercially and which is formed from either natural or synthetic fibersin the well-known manner. As is well known, such non-Woven textilematerial has many of the characteristics of paper except that is formedfrom textile fibers such as rayon, cotton, polyester, etc.

The strip 32 is unwound from a supply roll 33 and is impregnated with asuitable resinous material by advanc ing the strip 32 through areceptacle 34 containing an impregnating resin bath 36 as shown inFIGURE 2. Preferably, the resinous material 36 is any suitable resinwhich is provided in the form of an aqueous emulsion. The curing of thisresinous material 36 may therefore be accomplished by the evaporation ofthe water vehicle from the resin and water mixture. Guide rollers 37-40are suitably positioned as shown in FIGURE 2 adjacent the receptacle 34so that the strip 32 is immersed in the resinous emultion of the arrowI, it enters the cutoff device 18 in which it is cut into uniformsections which are removed for curing. Preferably these tube sectionsare formed approximately eight feet in length. The curing of thesections severed from the tube T is then carried out so that the watervehicle in the resin-water mixture in the tube outer ply 32 will beevaporated and the resin with which the tube T is impregnated will setpermanently. Using an aqueous resin mixture for impregnation of the tubeply 32 permits the curing to be accomplished under normal roomtemperatures over a relatively short period of time. However, if it isdesired to shorten the curing time by the application of heat, meanssuch as an oven can be utilized.

After curing, the tube sections are then cut into a plurality of shortlengths, preferably lengths of approximately eight inches to provideforming tubes 11 of a length suitable for use in a glass fiber windingand unwinding operation.

, forming tube of the invention simple and inexpensive in constructionso as to be low in initial cost but is capable of repeated use wth aminimum of wear. A particularly outstanding feature of the invention isthe use of non-woven textile material for the outer ply of the tubewhich when impregnated with resin has a high degree of resin absorptionso as to produce a particularly hard, irregularly roughened outersurface on the forming tube. The resin 7 in the non-woven textilematerial outer ply not only secures the outer ply to the underlyingpaper ply but when the resin has cured it produces an ideal surface forthe winding and unwinding of glass fibers.

While there has been described what at present is considered to be thepreferred embodiment of the invention, it will be understood by thoseskilled in the art that various changes and modifications may be madetherein without departing from the invention and, therefore, it is theaim of the appended claims to cover all such changes and modificationsas fall Within the true spirit and scope of the invention.

Having thus described the invention, what is claimed 1. A non-rigidforming tube for glass fibers comprising, in combination, at least onespirally wound inner ply" of paper and a spirally wound outer ply ofresin impregnated, non-woven textile material having a hard, irregularly roughened outer'surface for the winding of glass fibers, said plyof paper and ply of non-woven textile material having a thickness andcomposition for permitting said forming tube to flex readily andcollapse longitudinally for removal of the tube from a package of glassfibers wound thereon.

2. A non-rigid forming tube in accordance with claim 1 which includes apair of spirally wound inner plies of paper arranged in staggeredoverlapping relationship with adhesive therebetween, said plies of paperand non-woven textile material having a thickness and composition forpermitting said forming tube to flex readily and collapse longitudinallyfor removal of the tube from a package of glass fibers wound thereon.

3. A non-rigid forming tube in accordance with claim 2 wherein saidpaper plies are wound with the edges of adjacent convolutions inabutting relationship and wherein said outer ply of non-woven textilematerial is Wound with the edges of adjacent convclutions in overlappingrelationship.

4. A non-rigid forming tube in accordance with claim 2 wherein saidpaper plies and said ply of non-woven textile material are wound at awinding angle within the range of 3550 degrees.

5. A non-rigid forming tube in accordance With claim 4 wherein saidpaper plies and said ply of non-Woven textile material are Wound at awinding angle of about 40 degrees.

References Cited UNITED STATES PATENTS 347,416 8/1886 Buckingham 138-4192,945,638 7/1960 Crawford et a1. 242118.32

FRANK I. COHEN, Primary Examiner.

G. F. MAUTZ, Assistant Examiner.

1. A NON-RIGID FORMING TUBE FOR GLASS FIBERS COMPRISING, IN COMBINATION,AT LEAST ONE SPIRALLLY WOUND INNER PLY OF PAPER AND A SPIRALLY WOUNDOUTER PLY OF RESIN IMPREGNATED, NON-WOVEN TEXTILE MATERIAL HAVING AHARD, IRREGULARLY ROUGHENED OUTER SURFACE FOR THE WINDING OF GLASSFIBERS, SAID PLY OF PAPER AND PLY OF NON-WOVEN TEXTILE MATERIAL HAVING ATHICKNESS AND COMPOSITION FOR PERMITTING SAID FORMING TUBE TO FLEXREADILY AND COLLAPSE LONGITUDINALLY FOR REMOVAL OF THE TUBE FROM APACKAGE OF GLASS FIBERS WOUND THEREON.